compare.result

来自「这是linux下运行的mysql软件包,可用于linux 下安装 php + m」· RESULT 代码 · 共 45 行

drop table if exists t1;
CREATE TABLE t1 (id CHAR(12) not null, PRIMARY KEY (id));
insert into t1 values ('000000000001'),('000000000002');
explain select * from t1 where id=000000000001;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	PRIMARY	PRIMARY	12	NULL	2	Using where; Using index
select * from t1 where id=000000000001;
id
000000000001
delete from t1 where id=000000000002;
select * from t1;
id
000000000001
drop table t1;
SELECT 'a' = 'a ';
'a' = 'a '
1
SELECT 'a\0' < 'a';
'a\0' < 'a'
1
SELECT 'a\0' < 'a ';
'a\0' < 'a '
1
SELECT 'a\t' < 'a';
'a\t' < 'a'
1
SELECT 'a\t' < 'a ';
'a\t' < 'a '
1
CREATE TABLE t1 (a char(10) not null);
INSERT INTO t1 VALUES ('a'),('a\0'),('a\t'),('a ');
SELECT hex(a),STRCMP(a,'a'), STRCMP(a,'a ') FROM t1;
hex(a)	STRCMP(a,'a')	STRCMP(a,'a ')
61	0	0
6100	-1	-1
6109	-1	-1
61	0	0
DROP TABLE t1;
SELECT CHAR(31) = '', '' = CHAR(31);
CHAR(31) = ''	'' = CHAR(31)
0	0
SELECT CHAR(30) = '', '' = CHAR(30);
CHAR(30) = ''	'' = CHAR(30)
0	0